封装成了一个方法，方便其他地方用：
```javascript
// stringImg为图片路径序列
function downloadFile(stringImg) {
var arrImg = stringImg.split(",");
var index = 0;
var total = arrImg.length;
var down = function() {
var imgUrl = arrImg[index];
console.log(imgUrl)
var downLoader = plus.downloader.createDownload(imgUrl, {}, function(download, status) {
if(status == 200) {
plus.gallery.save(download.filename, function() {
console.log("success:" + imgUrl);
index += 1;
if(index !== total) {
down();
}
}, function(e) {
console.log("error:" + imgUrl + JSON.stringify(e));
});
}
});
downLoader.start();
};
down();
}
```
问题解决，非常感谢！！

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